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Comment by radarsat1 | Hacker News Reader

Weigh an SSD before and after storing data on it? That's so easy to do I have no idea why such an article would leave it as a theoretical.

edit: since I have been downvoted, perhaps someone would like to clarify how my description differs from, "taking mass measurements of a digital data storage device when it has full memory. If it has more mass than when the device’s memory is cleared, then that would show the mass-energy-information equivalence is correct."

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> Unfortunately, taking the extremely small measurement needed to such precision may currently be unachievable. Vopson proposes the next step to getting answers could be developing a sensitive interferometer similar to LIGO or an ultra-sensitive Kibble balance.

The article explains why it's not testable.

Or you could just store a crazy amount of information on one medium that's big enough. Can somebody calculate how much it would need to be before it's measurable with modern instruments?

From the paper:

> For 1Tb device the estimated mass change is 2.5 × 10^-25 Kg.

I don't actually know how precise we're currently able to measure mass, though.

A proton weighs ~10^-27 kg, so that's about 100 protons. I sincerely doubt we have masses that are quite that good - especially that which can take a high mass item (harddrive) and detect an atomic-scale change without being hideously noisy

it does not work that way because a SSD stores the information by capturing and binding electrons. Presence of an electron in the flip-flop (electric charge) is evaluated as 1 and non-existence of an electron is evaluated as zero.

A full SSD will be actually heavier :) but when you think about it the information amount is the same, a SSD with full zeroes and another one full with files have same amount of information equal to capacity of the SSD. Whether it is meaningful information or not is another discussion.

The last paragraph of TFA explains why it is left theoretical. In short, lack of measuring accuracy.

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